On September 11, 2001 American Airlines Flight 77, a Boeing 757 crashed into the Pentagon in Arlington, VA. A certified analog copy of air traffic control (ATe) transmissions recorded on September 11, 2001 at various tower, departure, and Air Route Traffic Control Center (ARTCC) positions along the route of flight was sent to the audio laboratory of the National Transportation Safety Board. These recordings were used to create an audio track and text transcript of the aircraft-ground communications from takeoff to accident time.

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D. DETAILS OF INVESTIGATION

Transmissions between the accident aircraft and ATC were recorded and an analog copy was sent to the Safety Board's audio laboratory. The tapes cover the following ATC positions and time periods:

Facility Time Period" (UTe) Position
lAD 1211 - 1226 LeW
1215 -1230 NO
1218 -1231 NH
ZOC 1220 -1236 Sector 05R
zoe 1226 -1246 Sector 03R
ZIO 1234 - 1309 HNN-R
1249 -1313 DAC-RA
1249 - 1313 DAC-R Sections of the tape recordings containing air-ground transmissions to and from the incident aircraft were digitized at a 22,050 Samples/second data rate and saved as standard Microsoft . way files. Individual . wav files were combined into a single 43 minute 59 second long . way file containing all transmissions to and from the incident aircraft from 1219:20 UTe (aircraft cleared for takeoff) to 1303:19 UTC. A transcript was obtained from the final composite recording. Times are approximate due to limitations inherent in the data obtained from the FAA.

Joseph A Gregor K( Electrical Engineer

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Transcript of ATe communications with a Boeing 8-757-200 (American Airlines flight 77) which crashed into the Pentagon in Arlington, VA on September 11, 2001.

LEGEND

AAL-77 Radio transmission from American 8-767-200. flight 77

LCW Radio transmission from Local Control West

NO Radio transmission from North Departure

NH Radio transmission from North High

05R Radio transmission from Sector 05 Radar position

03R Radio transmission from Sector 03 Radar position

HNN-R Radio transmission from Henderson Radar position

DAC-RA Radio transmission from DAC Radar Associate position

DAC-R

Radio transmission from DAC Radar position

*

Unintelligible word Expletive

#

Questionable insertion

[ ] Editorial insertion

Pause

Interruption

Note 1: Times are expressed in universal coordinated time (UTe).

Note 2: Only radio transmissions to and from the accident aircraft were transcribed.

Note 3: Words shown with excess vowels. letters. or drawn out syllables are a phonetic representation of the words as spoken.